The judge accused the tabloid - and its then-deputy editor Andy Coulson, who was jailed for 18 months - of chasing newspaper sales by withholding information about Milly's disappearance from Surrey Police detectives, until a potential scoop gleaned from hacking her voicemail had hit a dead end.

The Old Bailey trial heard a team of reporters was dispatched to Telford in April 2002 after an answerphone message revealed the 13-year-old had been inadvertently offered a job interview.

But the message was intended for another person with a similar name and number to Milly.

Coulson, from Charing in Kent, was in charge of the Sunday paper that week while editor Rebekah Brooks was on holiday in Dubai.

Mr Justice Saunders said: "Mulcaire picked up a message left on Milly Dowler's phone by an employment agency in Telford.

"We now know that the message was left to them by mistake on Milly's phone and was intended for someone who had a similar mobile phone number and name.

"The News of the World didn't know that, and a team of reporters were dispatched to find her. They failed. As we know, Milly was already dead.

"The News of the World delayed telling the police the contents of the voicemail until they realised that they were not going to find Milly.

"That was unforgivable and could only, in my judgment, have happened with the knowledge of the person editing the paper that week, Andy Coulson."

Andy Coulson was jailed for 18 months

The judge said Mulcaire had lied when he claimed to have hacked Milly's phone in order to help the police.

He said Mulcaire knew "perfectly well" that he was doing it to assist the News of the World in getting the scoop by finding her.

Mr Justice Saunders said: "The fact that they [the NotW] delayed telling the police the contents of the voicemail demonstrates that their true motive was not to act in the best interests of the child, but to get credit for finding her and thereby sell the maximum number of papers."

Coulson was jailed for 18 months after the 46-year-old father of three was found guilty of conspiring to intercept voicemails.

NotW news editor Greg Miskiw, 64, from Leeds, chief reporter Neville Thurlbeck, 52, from Esher, and news editor James Weatherup, 58, of Brentwood in Essex, were also sentenced after previously admitting one general count of conspiring together and with others to illegally access voicemails between October 2000 and August 2006.

Miskiw and Thurlbeck were each jailed for six months.

Weatherup was jailed for four months, suspended for 12 months, and ordered to do 200 hours' unpaid community work.

Mulcaire was jailed for six months, suspended for 12 months, and ordered to do 200 hours' unpaid community work.

The judge said Coulson clearly thought it was necessary to use phone-hacking to maintain the newspaper's "competitive edge".

He added: "Mr Coulson has to take the major shame for the blame of phone-hacking at the NotW. He knew about it, he encouraged it when he should have stopped it."

Rebekah Brooks was cleared of involvement in the phone-hacking conspiracy (Image: Mirror News)

According to Mulcaire's notes, Miskiw tasked him 1,500 times to carry out phone-hacking, Thurlbeck 261 times and Weatherup 157 times, the court heard.

Mulcaire, who was paid around £500,000, was first convicted of phone-hacking with royal reporter Clive Goodman in 2006.

Following a renewed police investigation into the full extent of hacking, he admitted three more counts of conspiring to hack phones plus a fourth of hacking the voicemail of Milly Dowler in 2002 - an act which eventually led to the closure of the NotW in 2011.

While Coulson was in charge, the NotW was hacking a host of royals, celebrities, politicians and ordinary members of the public on an industrial scale amid intense competition for exclusive stories, the trial heard.